Anti-Spam Group Says Cyber Attack Has Subsided

An anti-spam group says a large cyber-attack that slowed down parts of the Internet in recent days appears to have subsided.

The London-based group Spamhaus said in a web posting early Thursday that it was still seeing some "distributed denial of service" attacks on its computer servers, but the size of the attacks was smaller.

Spamhaus and the company it hired to fight cyber-attacks, Cloudflare, said the assault began on March 18 and appeared to originate with an anonymous group or individuals unhappy with efforts to block junk email, known as spam. Spamhaus said it had not identified the attackers.

Security engineers say the attack came from a network of thousands of computers that had been infected with a computer virus to become part of what is known as a "botnet," which then was used to send huge amounts of data to targeted servers in an effort to overwhelm them.

Spamhaus said the recent attack on its servers was the largest it had ever seen, and it said by attacking one link in the Internet infrastructure the botnet was able to slow down other parts of the Internet as well.